Web straps are commonly employed in cargo control systems for positioning cargo within a compartment, reinforcing material handling apparatus, or similar applications. Such cargo control systems commonly employ means for tensioning the web, and the ends of the web straps are provided with anchors for attaching the web loop end to support structure, usually a track or fittings defined in the side wall, floor or ceiling of a cargo compartment.
One type of web fitting developed by the assignee is shown in U.S. Pat. Nos. 2,984,885 and 3,017,679 wherein two side plates with a keeper plate located therebetween are mounted upon a web strap and the side plates include notches of different depth whereby the side plate notches may be inserted within an opening defined in a support member. The center keeper plate includes a latch tab which is capable of aligning with the side plate notches to interfere with removal of the side plates from the opening to prevent inadvertent release, and the keeper plate also includes a web receiving opening of greater width than that of the side plates whereby the keeper plate may be displaced to remove its latch tab from alignment with the side plate notches, and permit release of the fitting from the support member opening by a combination vertical and tilting movement of the fitting.
While the releasable fitting described above, and shown in the aforementioned patents, provides an economical manner to attach a web strap to a fixed location the orientation of the fitting to the support member is relatively fixed due to the interrelationship of the support member opening with the side plate notches. Accordingly, the fitting is unable to adapt itself to the direction of tension within the web, and web tension which is lateral to the plane of the fitting plates will produce lateral forces upon the plates, and possibly cause plate bending. Further, the inability of the fitting to move relative to the support member may cause the web loop to be crushed against the fitting outer edges by adjacent cargo or material handling apparatus loosely transported within a cargo compartment, and it is not uncommon for webbing to be damaged by being pinched against its fitting.
It is an object of the invention to provide an economical attachment fitting for webs utilizing a plurality of plates through which a web loop extends wherein the plates are articulated with respect to an anchor permitting swiveling of the plates relative to the anchor causing the fitting to align itself with the web tension or fold flat against the support member and thereby aid in protecting the webbing against damage by pinching.
A further object of the invention is to provide a releasable attachment fitting for webbing wherein three plates mounted upon a web loop are associated with an anchor in an articulated manner wherein the plates may swivel with respect to the anchor, and the plates include latching tabs defined thereon which are selectively disposed in a predetermined relationship to mounting surfaces defined upon the anchor such that the latching tabs will prevent accidental release of the anchor from its support member regardless of the position of the fitting plates relative to the anchor.
An additional object of the invention is to provide an attachment fitting for webbing wherein side and keeper plates are mounted upon a web loop, the keeper plate being displaceable with respect to the side plates and including a latching tab, and the side plates being loosely mounted upon a U shaped anchor for articulation thereto. The anchor includes locking projections for association with the opening of the support member, and the side plates include latching tabs, said latching tabs of said side and keeper plates selectively cooperating with the anchor locking projections in a predetermined manner to prevent inadvertent release of the anchor from the support member opening.
A further object of the invention is to provide a releasable attachment fitting for webbing wherein three plates mounted upon the webbing are associated with a U shaped anchor, and a keeper plate includes a recess for providing clearance with the anchor to permit use of the fitting with large dimensional anchor receiving openings in a support member.
In the practice of the invention the fitting includes two relatively flat side plates mounted upon opposite sides of a keeper plate, and the plates are supported relative to a U shaped anchor in an articulated manner wherein the plates, and associated webbing, can pivot with respect to the anchor. Each of the plates includes a web receiving opening through which a web extends defining a loop at the webbing end, and the web receiving opening of the keeper plate is greater than that of the side plates whereby a displacement of the keeper plate generally parallel to the plane of the side plates is possible.
The U shaped anchor, in one embodiment, is received within the web receiving openings of all three plates, and in another embodiment, is received within the web receiving openings only of the side plates and an anchor clearance is defined in the keeper plate. The anchor includes two sets of locking projections which are adapted to be inserted through the opening of a support member, such as a track, and the length of one set of projections is greater than that of the other. Upon tilting of the anchor to insert the longer set of projections into the opening the anchor may be displaced by sequential linear and tilting movement to insert both sets of projections into the support member opening, and the anchor is "locked" within the opening by latch tabs defined upon the side and keeper plates.
The side plates are each provided with a latch tab which transversely extends to the general plane of the associated plate in an outward direction, and is located adjacent an inner edge of the associated plate so as to lie within the plane of the opening of the support member in which the anchor is located. Likewise, the keeper plate includes a latch tab generally defined within the plane of the keeper plate which also extends into the support member opening receiving the anchor. The latch tabs of the side and keeper plates are all located adjacent each other within the support member opening, and the orientation of the latch tabs will insure that at least one tab is located in alignment with the plane of the support member opening regardless of the pivotal relationship between the plates and the anchor. To remove the anchor from the support member opening the fitting must be oriented such that the plane of the keeper plate is substantially perpendicularly disposed to the plane of the opening wherein only the keeper plate latch tab is located within the opening plane. The keeper plate may then be displaced between the side plates, upon loosening of the web loop to permit the keeper plate abutment to slide past inner edges of the side plates, and such displacement of the keeper plate removes its latch tab from the opening permitting the anchor to be raised, tilted and withdrawn from the opening.
The articulation of the plates of the fitting which engage the webbing with respect to the anchor minimizes the stressing of the webbing in that the plates will automatically align themselves with the tension within the web, and as the plates can fold back against the support member when no web tension is present the likelihood of crushing or pinching the web is reduced as compared with the prior art fittings of this general type.